1. Field of the Invention
The present invention relates to a LED device and a packaging method thereof. In particular, the present invention relates to a LED device with a high package efficiency and a stable color uniformity of the light emitted by the LED device, and a packaging method thereof.
2. Description of Related Art
LEDs have a numerous merits, such as small dimension, light weight, fast response, low power consumption, etc, and may be used as the light source of indicators, or displays, as well as other applications. Recently, white-light LEDs have been developed to be used as a light source to replace the tungsten lamp or fluorescent tube.
As shown in FIG. 1, which is a white-light LED of the prior art. A light-emitting chip 12 is located at the bottom of a concave portion 111 of a base 11 and a phosphor layer 13 is filled into the concave portion 111 to cover the light-emitting chip 12. By utilizing the phosphor powder 131 distributed in the phosphor layer 13, part of blue light emitted from the light-emitting chip 12 is converted into yellow light so that the yellow light and the unconverted blue light are mixed to form white light.
However, the white light emitted from the white-light LED may be shifted toward blue light or yellow light in some directions. Because the light path of the light beam L1 emitted from the top surface of the light-emitting chip 12 and the light beam L2 emitted from the side surface of the light-emitting chip 12 in the phosphor layer 13 are longer, the light beams L1, L2 may be converted into yellow light by the phosphor layer 13. Therefore, the light beam emitted from the side surface of the light-emitting chip 12 will be yellow-like so that the color uniformity of the light emitted by the white-light LED would be shifted toward yellow.